Well, I should be the one mentioning:

Beduin Camel Warriors

Ready to build from the beginning, these guys are mounted, have a good charge, they are cheap (even cheaper playing Egypt), they can take out cavalry, they can take out archers. If you use them properly, they can take out spears with a lot of flanking. Even though they usually lose out to infantry, they are faster than inf. and can meet them on their own terms always. I'd even say you could play a full campaign using nothing but camels.

I certainly underrated them in the past, but now I fancy them a little (but not in that way, you know)

But I'll also recommend Woodsmen! Trained in their bonus province (Lithuania?) and under a high-command general, these guys pack a punch, especially in the woods where spears and cavalry have a harder time. But they've never achieved anything for me in the center of a formation - flanking only...

/KotR